If you rendered an audio file, the last time you rendered, then you will only see the file types that you rendered last. You must select what you'd like to render to, first, before you can see other type files
ie: if you made some mp3's or wavs, last time you rendered, then the render window is still set to those audio files and won't list video, so if you're going to render to mp4 or whatever, select the render source, and then the other files will be visible.
Make sure "include audio" is checked in the render dialogue box.
What format are you rendering to? If it's a "stream" it may not have audio.
When you post on a forum for help, you should provide as much detail as possible; like all your settings. Otherwise, it will take a lot longer to find the solution.
Please forgive me if the following is something you are painfully aware of (or I'm not understanding your problem). Since you reference mp4, m2ts I'm guessing that you want to render to the Sony (or possibly MainConcept) encoders. Make sure that has been selected in the "Save as Type" option. If you have inadvertently selected an Audio Encoder, you will only get Audio render Templates.
Yeah Thats the file type i want to save it as but its not there. also vegas is telling me to put in my verification code again for some reason but i have no idea what it was
To find your serial number (I assume that's what's meant by the "verification code"), go to "My Account" at the top of this screen. Click on "My Software", enter your site password. The code should be displayed.